A girl as young as 8 is believed to be responsible for a bomb attack on a Nigerian market in which five were killed and dozens injured as defeated Boko Haram militants flee the region.

The attack took place at a security check outside a market in the northeast Nigerian town of Potiskum earlier today, Reuters reports.

It’s the third incident this year in which children have been used to carry out attacks in Nigeria, a nation stricken by violence from home-grown Islamic extremist group Boko Haram.

It comes as insurgent militants flee the region after suffering a heavy defeat to Government forces from four nations bordering the town of Baga – Nigeria, Cameroon, Niger and Chad.

A witness told Reuters that the girl, strapped with explosives, “let the bomb off, killing herself and five others, while many were injured”.

Resident Bala Totiskum said he saw dozens of wounded being rushed to hospital after the blast.

Both witnesses told Reuters that the bomber was “a small girl”, estimating that she can’t have been more than 8 years old.

No-one has yet claimed responsibility for the attack, but it carries the hallmarks of Boko Haram, which is believed to be responsible for a string of attacks in the region using children.

Earlier this month, a 16-year-old blew herself up at a crowded bus station, also in north-eastern Nigeria. Sixteen people were killed and Associated Press reported that witnesses said many of them were children who had either been selling peanuts or begging for money.

In January, the BBC reported that 19 people were killed in Maiduguri market, also in the North East, after a bomb was strapped to a girl believed to be around ten years old.

The market is reported to have been targeted twice in a week by female bombers last year.

Boko Haram, believed to be responsible for the attack today, recently suffered a heavy defeat as the Nigerian Army reclaimed the town of Baga, also in the north east, where the bombing took place.

The official Nigerian Army twitter account tweeted: “Military Operations in Monguno and other communities successful. God bless the Armed Forces of Nigeria.”

Islamic militants had held the town since January 3rd. The Nigerian Government claims that 150 people were killed when they took Baga and nearby Doron Baga, but locals told the BBC that the number could be as many as thousands.

But Nigerian forces, with help from its neighbours and backed by airstrikes, seized to north eastern town on Saturday, in what the military called a significant victory against insurgency.

“We have secured Baga. We are now in full control. There are only mopping up exercises to do,” Defence Spokesman Major-General Chris Olukolade told Reuters.

He added that “a large number of terrorists had drowned in Lake Chad”, as they fled from military advances from the African nations.

Baga was the headquarters of an international force for all four countries and its recapture was an important one. Boko Haram forces are said to now be on the run, in this region and many others.

Olukolade added: “Not even the strategy of mining over 1,500 spots with land mines on the routes leading to the town could save the terrorists from the aggressive move of advancing troops.”

The victory comes at an important time for President Goodluck Jonathan, who is up for election on March 28th after a six-week delay, on the grounds that more time was needed to fight insurgents.

It will be welcome opportunity to talk of success after a bloody battle with Islamists in which thousands killed and 1.5-million were displaced last year alone.

Over the six-year conflict, the Suni group has killed thousands more and kidnapped hundreds, with successes in the last year that saw them carve up territory the size of Belgium.

But fleeing Boko Haram forces are often seen as dangerous to the general population. Reuters reported that militants retreating from an offensive in Sambisa killed 21 people on Friday in attacks near Chibok, where rebels abducted 200 schoolgirls last year.

Military chiefs will meet in Chad’s capital N’Djamena next week to finalist plans for an 8,700-strong task force of troops from the four countries, plus Benin.